Apparatus for producing a heat-sealable container

ABSTRACT

In a process for making a filled and closed container of heat-sealable plastic hose, in one work operation, the hose is expanded to become a container body, the body is filled and the upper part of the container is shaped when the container is closed. After the filling process and before closing, the upper part of the container is closed by a rubber stopper. An apparatus to carry out the process includes a container-molding appliance having a lower and upper mold parts, with a mold holding fixture in each of the upper parts which can be displaced in the direction of movement of the upper mold part and be moved automatically opposite the upper mold part, and with a holding device inside the plastic hose which can be moved vertically. The holding device releasably holds the rubber stopper for insertion into the completed container body. The holding device is attached to a cross slide which permits horizontal movement, so that the rubber stopper can be moved from a receiving location to the container being formed.

This invention relates to a process and apparatus for producing acontainer from a hose or tube of heat-sealable synthetic polymericmaterial such as polyethylene, the container being filled, provided witha stopper and heat-sealed closed in one work operation, and to acontainer made by the process and apparatus.

BACKGROUND OF THE INVENTION

A container having a predetermined, lasting shape can be produced usinga known process and known apparatus as described in German AS No.2,255,869 and employing a calibration pin in the area of the head of thecontainer.

It is also known to produce, fill and close a container in one workoperation, using a heat-sealable plastic hose, wherein a rubber stopperis inserted in the bottom of the container in such a way that thestopper is surrounded by the material of the container only on its outercircumference, leaving the outside face of the stopper exposed, as aconsequence of which the stopper can get dirty. The stopper is notinserted or seated in the container tightly enough, with the result thatbacteria from the outside can grow into the container.

It is also known to produce a filled and closed container the head ofwhich contains an inserted rubber stopper which is closed off completelyfrom the outside by the container. However, that container is made oftwo parts which are joined together after the manufacture, filling andclosing of the major, bulging body portion of the container with thehead which receives the rubber stopper being welded to the closed,bulging portion of the container. In this arrangement, even when abreakable seal is used, the closed bulging portion of the container mustbe pierced by the injection needle during use which can result incutting out a part of the material of the bulging portion of thecontainer and clogging of the injection needle.

BRIEF DESCRIPTION OF THE INVENTION

An object of the invention is to provide a method of forming a filledand closed container having a rubber stopper wherein the container isformed and closed in one work operation, and is of seamlessconstruction.

Briefly described, the invention includes a process for the manufactureof a filled and closed container made from a heat-sealable hose ofpolymeric material such as polyethylene in a single operation of thetype wherein the hose is expanded to become a container, the bodyportion of the container is filled and its upper head portion is shapedwhen the container is closed, comprising the steps of inserting a rubberstopper into the head portion after the container portion is filled andbefore the head portion thereof is closed so that the stopper closes offthe lateral section of the container and a portion of the stopperextends into the head portion which is still to be shaped, shaping thehead portion surrounding the rubber stopper so that at least part of thematerial of the head portion conforms to and encloses the outercircumference of the stopper, and sealing the outer portion of the headportion outside of the stopper.

In another aspect the invention comprises an improved apparatus forforming, filling and closing a container by expanding and shaping aheat-sealable polymeric hose, the apparatus being of the type having acontainer-forming mold with split upper and lower parts, and amold-holding fixture for each of the upper mold parts movable inopposite directions, the improvement comprising means movable at leastvertically to within the hose for releasably holding a rubber stopper; across slide for supporting said means for holding said stopper forhorizontal movement relative to said mold, whereby said means forholding can be moved to a receiving position for engaging a stopper andto a position in said hose for placing the stopper therein.

The invention also includes a filled container made of thermoformablepolymeric material comprising a body portion, a head portion and astopper wherein said stopper is inserted into said body portion inclosing relationship therewith after forming and filling said bodyportion, and said head portion is shaped around the circumference ofsaid stopper and sealed to enclose said stopper, said container being ofunitary seamless construction.

In order that the manner in which the foregoing and other objects areattained in accordance with the invention can be understood in detail,particularly advantageous embodiments thereof will be described withreference to the accompanying drawings, which form a part of thisspecification and wherein:

FIG. 1 is a partial side elevation, in partial section, of an apparatusin accordance with the invention along line I--I of FIG. 2;

FIG. 2 is a partial top plan view of the apparatus of FIG. 1;

FIG. 3 is a front elevation, in partial section, of a container inaccordance with the invention; and

FIG. 4 is a side elevation of the container of FIG. 3.

As will be recognized by those skilled in the art, a portion of theapparatus employed in accordance with the present invention is knownfrom, for example, the previously mentioned German AS No. 2,255,869, andincludes two lower mold parts 1 and 1a which are horizontally movableand which can be opened and closed, the mold halves 1, 1a beingsupported respectively on plate-like supporting pieces 2 and 2a whichcan be moved toward and away from each other by arrangements such aspiston and cylinder assemblies, not shown. A vacuum holding fixturehaving portions 3, 3a is fastened to the upper ends of both of thecontecting pieces 2, 2a. Vacuum holding fixtures 3, 3a describe a circleand extend up to each other. Between lower mold part and vacuum holdingfixture 3, is positioned a top mold part 5 which is attached to a pistonrod 4 passing through connecting piece 2 and being connected to a pistonand cylinder arrangement, not shown, which is positioned in such a waythat mold portion 5 can be moved horizontally. Similarly, between lowermold part 1a and vacuum holding fixture 3a, there is a top mold part 5awhich is also fastened to a piston rod 4a of a piston and cylinderassembly, not shown.

As shown in FIG. 2, the production mold including components 1-5 and1a-5a is used for simultaneously manufacturing two bottle-shapedcontainers of the type illustrated in FIGS. 3 and 4.

A blowing and filling mandrel 6 which can be raised and lowered isprovided above the production mold and it can be located on a specialsupport (not shown) or on a permanent bridge 7, in the form of a frame,to which an extruder (not shown) is also fastened.

Bridge 7 supports a piston and cylinder assembly 9 having a verticalworking axis which is supported on a transverse strut 8 with the pistonrod of the piston and cylinder assembly being attached to a verticallyslideable carriage 10. Guide bars 11 which are attached to oppositesides of strut 8, serve as guides for the movement of carriage 10.

A further piston and cylinder assembly 12 disposed to operate in ahorizontal axis is attached to the vertically slideable carriage 10, thepiston rod of assembly 12 passing through carriage 10 and beingconnected to a horizontally slideable carriage 14 which is guided byhorizontally extending guide bars 13. A limiting element 15 is fastenedto bridge 7 and serves to limit the extent of downward movement ofcarriage 10 and works together with horizontally slideable carriage 14in one end position, as illustrated, but is inactive when carriage 14 isin its other end position.

A peg-shaped holding device 17, disposed along a vertical axis, isattached to the horizontally slideable carriage 14, on the end thereofopposite assembly 12, by means of a support 16, the holding devicehaving a central conduit which can be selectively connected to a vacuumsource, the conduit terminating in an inwardly extending recess shapedand dimensioned to receive a portion of a rubber stopper 18. Thestopper, which is held by a collar, is disposed in a receiving positionin a hole in a delivery slide 19. Because the production mold has twoworking cavities, a holding device 17 and a delivery slide 19 with ahole therethrough to receive a rubber stopper 18 is provided for eachworking cavity.

A rectangularly shaped limiting element is fastened to support 16between the two holding devices 17 and, when the holding devices aremoved to their operative positions in the molds, engages in recesses 21and 21a of lower mold parts 1, 1a and limits the displacement movementof the top mold parts 5 and 5a toward each other.

Delivery slide 19 can be displaced horizontally in a directionperpendicular to the direction of movement of horizontally slideablecarriage 14 by means of a horizontally disposed piston and cylinderassembly 22 (FIG. 2) and, as shown in FIG. 1 for stopper 18, it has arecess for each of the two rubber stoppers which it receives. The tworecesses can be delivered one after the other under conveyor strip 23which is supported, or forms part of, a vibration conveyor, not shown,from which two rubber stoppers 18 are delivered to delivery slide 19with each work operation. The top of conveyor strip 23 is covered.

The lowered part of blowing and filling mandrel 6, vertically slideablecarriage 10, horizontally slideable carriage 14, the two holding devices17 and conveyor strip 23, as well as the individual componentsassociated with them, are located in a chamber which is enclosed andsealed on all sides by sheet metal housing 24, the upper part of thechamber not being visible in the drawings. Sheet metal housing 24, aswell as conveyor strip 23, can be charged with a sterilizing agent suchas super heated steam, a disinfection liquid, sterilizing gas, or thelike for initial and continuous sterilization so that sterile filling ofthe container with filling material (FIGS. 3 and 4) and thesterilization of the rubber stoppers 18 located in strip 23 is possible.

The filled and closed container 25 is shown in FIGS. 3 and 4, the toppart of the container having a breakable closing device 26 and a rubberstopper 18 which is inserted in the top part, or head, of the containerentirely enclosed by material of the container 25. The top part of thecontainer fits against the outside of the rubber stopper up to a middleportion which is accessible after the breakable closing device 26 hasbeen broken off, so that rubber stopper 18 can be pierced directly by aninjection needle or the like.

To manufacture container 25, a parison is formed, the parison being alength of hose of polymeric material, such as polyethylene, which isextruded by an extruder, not shown, and grasped at its upper end byvacuum holding fixtures 3, 3a and lower mold parts 1, 1a, and theportion of the plastic hose located in and between the lower mold halves1, 1a is inflated until it constitutes the bulging portion, or body, ofa container. The body of the container is then filled with a fillingmaterial, the blowing and filling being accomplished through mandrel 6.After the body of the container is filled, rubber stopper 18 which isheld by holding device 17 is inserted in the upper part of the body ofthe container. This is accomplished by the holding devices 17 eachreceiving a rubber stopper from delivery slide 19 by lowering carriage10 until carriage 14 strikes the limiting element 15, whereupon holdingdevices 17 are again raised. The holding devices 17 are then movedhorizontally into a coaxial position with the body of the container andwith the remaining, unshaped, plastic hose which extends upwardly fromthe formed body, by displacing the horizontally slideable carriage 14.The holding devices are then lowered until the rubber stoppers carriedthereby assume the position shown in FIG. 1 in which each stopper is inthe upper part of the completed container body. The top mold parts 5, 5aare separated to their open positions as shown in FIG. 1 during thisportion of the operation.

Inside each of the upper mold parts 5, 5a is a mold holding fixture 25,25a which can be displaced parallel to the axis of piston rod 4 or 4a. Aspring 26 is inserted between mold holding fixture 25 and top mold part5, and it urges molding fixture 25 in the direction of fixture 25alocated opposite it, a spring 26a accomplishing the same task on theother side of the top mold structure. The extent of movement throughwhich fixtures 25, 25a are displaced in mold part 5 or 5a is terminatedby a mechanical stop member.

After the rubber stopper 18 has been inserted in the previously formedbody portion of the container and in the as yet unshaped portion of theplastic hose, the top mold parts 5, 5a are moved toward each other untilthey engage the limiting element 20 which is located, as previouslydescribed, between the two holding devices 17 which remain, at thisstage, in the unformed portion of the hose. Element 20 simultaneouslycatches in recesses 21, 21a of lower mold parts 1, 1a. As a result, therunning together of mold parts 5, 5a is limited. Mold holding fixtures25, 25a however, can come sufficiently close to each other, that underthe action of springs 26, 26a they engage the outer circumference of theheat-sealable plastic hose and a part of the top of the rubber stopperwhich has a projection in the middle of its upper face which remainsfree.

After the piston and cylinder assembly associated with rods 4, 4a havebeen relieved of their load, limiting element 20 can be removed from itsposition between upper mold parts 5, 5a by raising the holding devices17. The upper mold parts then close, and the part of the head ofcontainer 25 having the breakable closing device is produced byapplication of an external vacuum. The containers manufactured in thetwo mold working cavities are ejected by opening the upper and lowermold part 1, 1a and 5, 5a and also the vacuum holding fixtures 3, 3aallowing the formed, filled and sealed containers to drop out.

Although the embodiment described herein has two working cavities, itwill be apparent that any number of cavities can be used.

It will also be recognized that the mold holding fixtures 25, 25a can bemoved by means of piston and cylinder assemblies coupled thereto, inwhich case springs 26, 26a can be omitted.

As will be seen, the simple manufacturing process described herein callsfor a less complicated apparatus, and consequently an apparatus which isless susceptible to trouble. The rubber stopper is introduced into theplastic hose in a work operation carried out between the filling andclosing of the container and, when the container is finished, it isclosed off completely from the outside by the container material so thatno subsequent contamination of the rubber stopper can take place. Whenfilling is carried out in a sterile manner, the sterility of thecontents of the container continues to exist for a long time. Ifrequired, the container can be again sterilized subsequently. If thecontainer has a breakable closing device providing free access to therubber stopper, it is not necessary to pierce the head of the containerwith an injection needle.

While certain advantageous embodiments have been chosen to illustratethe invention it will be understood by those skilled in the art thatvarious changes and modifications can be made therein without departingfrom the scope of the invention as defined in the appended claims.

What is claimed is:
 1. An apparatus for forming, filling and closing acontainer by expanding and shaping a heat-sealable polymeric hose, theapparatus comprisinga container-forming mold with split upper and lowerparts, and a mold-holding fixture for each of the upper mold partsmovable in opposite directions; means movable at least vertically insidethe hose for releasably holding a rubber stopper; a cross slide forsupporting said means for holding said stopper for horizontal movementrelative to said mold; and means, carried on said cross slide andoperatively associated with said means for holding said stopper, forestablishing a predetermined position of the upper mold parts after saidstopper is introduced into the hose; whereby said means for holding canbe moved to a receiving position for engaging a stopper and to aposition in the hose for placing the stopper therein.
 2. An apparatusaccording to claim 1 comprising a slide for carrying a rubber stopperinto said receiving position.
 3. An apparatus for forming, filling andclosing a container with a stopper by expanding and shaping aheat-sealable polymeric hose completely about the stopper, the apparatuscomprisinga container-forming mold with split upper and lower parts anda mold-holding fixture for each of the upper mold parts movable inopposite directions; filling means for supplying contents to the hosewhile in said mold; stopper handling means, movable at least verticallyinside the hose from above said mold after filling the container, forreleasably holding a rubber stopper; and a cross slide for supportingsaid stopper handling means for horizontal movement relative to saidmold; whereby said stopper handling means can be moved to a receivingposition for engaging a stopper and to a position in the hose forplacing the stopper therein.
 4. An apparatus according to claim 3wherein said cross slide carries stop means, operatively associated withsaid stopper handling means, for holding said upper mold parts in apredetermined position after the stopper is introduced into the hose andbefore the stopper is released from said stopper handling means.
 5. Anapparatus according to claim 4 wherein a slide carries the rubberstopper to said receiving position.
 6. An apparatus according to claim 4wherein each of said upper mold parts comprises first and secondrelatively movable sections, said first sections having means formolding a container head and said second sections having means formolding the hose to the stopper.
 7. An apparatus according to claim 6wherein said stop means engages said first sections to position saidupper mold parts.
 8. An apparatus according to claim 6 wherein springmeans resiliently bias said first and second sections of each of saidupper mold parts.
 9. An apparatus according to claim 3 wherein each ofsaid upper mold parts comprises first and second relatively movablesections, said first sections having means for molding a container headand said second sections having means for molding the hose to thestopper.
 10. An apparatus according to claim 9 wherein spring meansresiliently bias said first and second sections of each of said uppermold parts.
 11. An apparatus according to claim 3 wherein a slidecarries the rubber stopper to said receiving position.
 12. An apparatusaccording to claim 3 wherein said mold comprises means for retaining thestopper in position in the hose and means for molding the hosecompletely about the stopper.
 13. An apparatus for forming, filling andclosing a container by expanding and shaping a heat-sealable polymerichose, the apparatus comprisinga container-forming mold with split firstand second parts and a mold-holding fixture for each of the first moldparts movable in opposite directions said first parts having means formolding the hose to the stopper and being relatively movable relative tosaid second parts; stopper handling means, movable at least verticallyinside the hose, for releasably holding a rubber stopper; and stopmeans, operatively associated with said stopper handling means, forholding said first mold parts in a predetermined position after thestopper is introduced into the hose and before the stopper is releasedfrom said handling means.
 14. An apparatus according to claim 13 whereineach of said first mold parts comprises first and second relativelymovable sections, said first sections having means for molding acontainer head and said second sections having means for molding thehose to the stopper.
 15. An apparatus according to claim 14 wherein saidstop means engages said first sections to position said first moldparts.
 16. An apparatus according to claim 14 wherein spring meansresiliently bias said first and second sections of each of said firstmold parts.